For me, I have zero intention of transferring anything off the disposable vanilla accounts, hence why I'd call them disposable. So no, it's cheaper to use vanilla WoW RAF's x 4 in conjunction with 4 of my primary accounts.
And as was posted above, in 3.3 they are nerfing AOE so boosting when CC hits won't be nearly effective as it currently is.
http://www.worldofwarcraft.com/patch...atchnotes.html
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